Insertion of a guide wire into a blood vessel is carried out roughly in the following manner. First, a cannula is inserted into a blood vessel, followed by insertion of a guide wire into the cannula. Then, the guide wire is pushed ahead and inserted into the blood vessel.
A known guide wire supply tool (guide wire inserter) used when inserting the guide wire into a blood vessel includes: a guide wire housing portion which is constituted by a wound tube and which houses a guide wire in the lumen thereof, and a feeding-out portion which is constituted by a tube body placed at one opening portion of the guide wire housing portion and by which the guide wire passing-through the tube body is to be fed-out. An example of this is disclosed in Japanese Unexamined Patent Publication No. 2004-290395. With respect to this guide wire supply tool, when the guide wire is unused (is not fed-out yet), it becomes in a state in which the distal portion of the guide wire protrudes from the distal opening of the feeding-out portion. Therefore, the feeding-out portion is attached with a tubular cap which covers the distal portion of the guide wire from the outside thereof.
The attachment between the feeding-out portion and the cap depends on only the friction between the outer circumferential portion of the feeding-out portion and the inner circumferential portion of the cap. In the event an external force of vibration or the like acts on the cap, the cap can become detached from the feeding-out portion. When the cap is detached from the feeding-out portion, the distal portion of the guide wire protruding from the feeding-out portion may be exposed, undesirably deformed and contaminated. In addition, in a case in which an external force acts on the cap, it sometimes happens that the distal portion of the guide wire vibrates and collides with the inner circumferential portion of the cap, possibly deforming the distal portion of the guide wire.